Small linear thermistors reach new thermal limits
Texas Instruments (TI) has expanded its temperature sensing portfolio to include linear thermistors that deliver up to 50% higher accuracy than negative temperature coefficient (NTC) thermistors. The higher accuracy of TI’s thermistors enables operation closer to the thermal limits of the other components and the overall system, helping engineers maximise performance while reducing bill-of-materials (BOM) and total solution cost.
NTC thermistors are widely used due to their low price; however, they present several challenges to design engineers, including degraded performance at temperature extremes and complex calibration requirements, which increases design time. TI’s new linear thermistors are available at a similar price while providing significantly more value – most notably minimising design time, reducing component count and increasing system performance.
TI’s new thermistors deliver reliable, highly accurate thermal measurements, particularly at temperatures above 80°C. This is especially important for industrial, automotive and consumer applications where precise, real-time temperature readings are fundamental to system performance and protection.
NTC thermistors provide less accurate temperature readings due to their low sensitivity and high resistance tolerance at temperature extremes. To compensate for these challenges, many engineers calibrate at three points across the temperature range or use multiple thermistors to monitor different temperature ranges. These approaches can still produce unreliable temperature readings, which can require systems to shut down before reaching their true thermal limit. The linearity and high accuracy of TI’s thermistors enable single-point calibration, which maximises system performance and simplifies design.
TI’s thermistors also offer very low typical drift of 0.5% to improve the reliability of temperature measurements, enabling designers to boost system performance while maintaining safe operation. Engineers can use TI’s thermistor design tool, available on the thermistor product pages and data sheets on TI.com, to quickly and easily calculate temperature resistance values and kick-start their design with example conversion methods and code.
By eliminating the need for additional linearisation circuitry or redundant NTC thermistors, TI’s thermistors help engineers simplify design, lower system cost and reduce printed circuit board (PCB) layout size by at least 33%, compared to NTC thermistors. In addition, TI’s thermistors are one-tenth the size of similar silicon-based linear thermistors, with a low profile and small package area that enable placement closer to thermal hot spots for faster thermal response and more consistent temperature measurements.
TI’s new thermistor portfolio, which includes the TMP61, TMP63 and TMP64, is available now through TI and authorised distributors with starting prices as low as $0.05 in 1,000-unit quantities. The devices are offered in through-hole packaging and surface-mount 0402 and 0603 footprint options.